A child in West Texas has died of measles, state health officials said on Wednesday, the first reported U.S. death from the highly contagious disease in a decade, as a Texas outbreak has grown from a handful of cases to more than 130 across two states.

At least 124 cases have been identified in Texas since late January, mostly among children and teenagers who are unvaccinated or whose vaccination status was unknown.

A child who was not vaccinated has died from measles in West Texas. It's the first death in an outbreak that began late last month and the first from measles in the U.S. since 2015.